added support for variable intervals

readme.md

@@ -11,13 +11,13 @@ Open source hardware TOTP token. Currently targets the LPC1756, LPC1758 and LPC1
 * support to change the RTC calibration values in the settings
 * support for setting the time + timezone (currently only GMT)
 * 60 seconds screen timeout
+* support for different intervals (supports 1 - 180 seconds)
 
 ### Images
 Images can be found in the project logs at [hackaday](https://hackaday.io/project/194867-hardware-2fa-totp-authenticator)
 
 ### TODO
 * encrypt profiles
-* support for different intervals
 * add support for more than 32 profiles (needs a rework if more profiles are required. The profiles are copied to ram and there is not enough for more at the moment. If we leave them in flash we can store a lot more)
 * rework the calibration and time settings screens
 

ui/config.hpp

@@ -631,7 +631,17 @@ namespace menu {
                 (*interval_end) = 0x00;
 
                 // convert the string to a number
-                ret.interval = klib::string::stoi(str_end + 1);
+                const uint32_t interval = klib::string::stoi(str_end + 1);
+
+                // check if the interval is valid
+                if ((interval > 180) || (!interval)) {
+                    // invalid, interval is too high or too low. clear the buffers and go to the next one
+                    buffer.clear();
+
+                    continue;
+                }
+
+                ret.interval = interval;
 
                 // get the length of the interval
                 auto digits_end = std::find(interval_end + 1, (buffer.data() + buffer.size()), ',');

ui/totp.hpp

@@ -62,8 +62,8 @@ namespace menu {
         };
 
         template <typename T, typename G> 
-        void draw_timer(FrameBuffer& frame_buffer, const klib::vector2i position, const klib::time::ms time, const T sin, const G cos) {
-            for (uint32_t i = (time.value * (sin.size / 30)) / 1000; i < sin.size; i++) {
+        void draw_timer(FrameBuffer& frame_buffer, const uint32_t interval, const klib::vector2i position, const klib::time::ms time, const T sin, const G cos) {
+            for (uint32_t i = (time.value * (sin.size / interval)) / 1000; i < sin.size; i++) {
                 const uint32_t index = (sin.size + ((sin.size / 4) * 3) + i) % sin.size;
 
                 const klib::vector2i p = position + klib::vector2i{
@@ -99,12 +99,12 @@ namespace menu {
                 case storage::digit::digits_6:
                     return klib::crypt::totp<hash, 6>::hash(
                         reinterpret_cast<const uint8_t*>(entry.key.data()), 
-                        entry.key.size(), current.value, 30, 0
+                        entry.key.size(), current.value, entry.interval, 0
                     );
                 case storage::digit::digits_8:
                     return klib::crypt::totp<hash, 8>::hash(
                         reinterpret_cast<const uint8_t*>(entry.key.data()), 
-                        entry.key.size(), current.value, 30, 0
+                        entry.key.size(), current.value, entry.interval, 0
                     );  
             }
 
@@ -185,7 +185,10 @@ namespace menu {
                 klib::string::itoa(last_epoch.value, epoch_buf);
 
                 // update the seconds left in this cycle
-                klib::string::itoa(30 - (last_epoch.value % 30), seconds_left_buf);
+                klib::string::itoa(
+                    entries[current].interval - (last_epoch.value % entries[current].interval), 
+                    seconds_left_buf
+                );
 
                 // the time has changed. Mark the totp as changed
                 // to force a update on the buffers
@@ -205,7 +208,7 @@ namespace menu {
 
                 // get the next token
                 const uint32_t next_token = get_token(
-                    entries[current], last_epoch + klib::time::s(30)
+                    entries[current], last_epoch + klib::time::s(entries[current].interval)
                 );
 
                 // copy the token to the buffer and set the width
@@ -307,11 +310,11 @@ namespace menu {
 
             const klib::time::ms runtime = (
                 klib::io::systick<>::get_runtime() - last_update
-            ) + klib::time::s(last_epoch.value % 30);
+            ) + klib::time::s(last_epoch.value % entries[current].interval);
 
             // draw all the circles
             for (uint32_t i = 0; i < sizeof(lookuptable_sin) / sizeof(lookuptable_sin[0]); i++) {
-                draw_timer(frame_buffer, position, runtime, lookuptable_sin[i], lookuptable_cos[i]);
+                draw_timer(frame_buffer, entries[current].interval, position, runtime, lookuptable_sin[i], lookuptable_cos[i]);
             }
 
             // draw the time left in seconds in the circle